API Reference > geometry-core > Curve > DirectSpiral3d > createChineseCubic createChineseCubic MethodStatic Create a Chinese clothoid approximation X is 2 terms of the clothoid series as a function of nominal distance along Y is 2 terms f the clothoid series as a function of nominal distance along Remark: This is identical to the Arema spiral createChineseCubic(localToWorld: Transform, nominalL1: number, nominalR1: number, activeInterval?: Segment1d): undefined | DirectSpiral3d Parameter Type Description localToWorld Transform axes with inflection at origin, tangent along x axis nominalL1 number nominal length as used in series LR terms. nominalR1 number nominal final radius as used in series LR terms activeInterval Segment1d fractional interval with (0, nominalL1) range for nominal distance along Returns - undefined | DirectSpiral3d Defined in curve/spiral/DirectSpiral3d.ts Line 363 Last Updated: 12 June, 2024